Investments - Offsetting of Assets and Liabilities (Details) - Free-standing derivatives - USD ($) $ in Millions	Jun. 30, 2022	Dec. 31, 2021
Asset derivatives:
Gross Amounts	$ 1.6	$ 10.7
Gross Amounts Offset in the Consolidated Balance Sheets	0.0	0.0
Net Amounts of Assets/ Liabilities Presented in the Consolidated Balance Sheets	1.6	10.7
Gross Amounts Not Offset in the Consolidated Balance Sheets, Financial Instruments	0.8	4.5
Gross Amounts Not Offset in the Consolidated Balance Sheets, Cash Collateral Received	0.4	6.4
Net Amount	$ 0.4
Net Amount		$ (0.2)

Fair value of liability associated with financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset.

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